sbt insulating shutters - goozmo, boulder colorado … · temporary plywood) zdecoration ......

Exterior Insulating Shutters

New Technology Under Development Enhances Performance in

New and Retrofit Buildings

Larry Kinney, Gary Cler, John Hutson,Ross McCluney

Synergistic Building Technologies, Inc

Synergistic Building Technologies2

Exterior shutters in wide use in Europe; some nice ones in Nice


Paris…elegance, grace, shading, ventilation, but very little insulation


In the US, shutters have moved from functional to merely ornamental. Why?

Energy is cheap, why bother with shutters that actually work?It’s a pain to actuate outsider shutters, particularly in the midst of cold wintersLots of windows would entail lots of opening and closingReal shutters would cost more than plastic ones anyway.


Nonetheless, functional, well-designed exterior shutters could perform well, providing:Security (now provided by glass, alarms, iron bars)Shading for solar control, napping (now provided by interior shades)Privacy (now provided by interior shades)Protection from the elements (double pane or temporary plywood)Decoration (functional shutters could do it, too)


SBT’s exterior-mounted insulating shutters have many advantages

Offer superior energy performance, both summer and winter Provide privacy and security; noise and light attenuation allowing sleep during the day if desiredAre fire and hurricane resistant Have aesthetic and architectural appealStore easily in plain sightAutomatic, wireless operation Avoid moisture problems on inside sills, a serious problem for inside-the-window insulation in winterAdaptable to many window sizesApplicable to new and retrofit housing


Installation on vintage country home (two real photos digitally combined)


The French know that shutters make sense; this one also saves Euros


Energy considerationsAssume energy-efficient housing whose walls are R 25, U = 0.5 windows and the window area = 16% of wall area. The energy loss through the windows is 2.38 times the energy loss through R-25 wall sections.When shutters are shut, the window system R value goes from 2 to 10 to 15 or even more.With shutters closed, losses through the windows drops to 0.48 that of wall sections, comfort is increased, as is privacy and security.Similar results during heating and cooling seasons.


Key to following slide on energy performance

Careful hourly simulation (using RESFEN Software) of six fenestration systems in six Southwestern cities; 75 sq ft of fenestration on each facadeIn conjunction with shutters that just meet code, shutters used during evenings and selectively during summer days outperform the best of the restFull report downloadable at www.SynergisticBT.com


Simulation results

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Clear 2 pane Low SHGC 2 paneShaded Low SHGC 2 pane Better Low SHGC 2 paneHi perf 3 pane Low SHGC + shutters


Key to following two slides

Slides show results of study of windows and shutters published in the Spring edition of the Boulder Green Building Guild (downloadable at www.SynergisticBT.comunder Insulating Shutters)Hourly simulation using RESFEN for the case of Denver, Colorado under conservative assumptions.


Denver weather, winter only

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Alpen TC88krypton

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Performance by direction

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OptionsIn most retrofit circumstances, shutters will be priced to have an installed cost of about the same as new windows, but the resulting energy performance will far exceed that of new windows.Savings and paybacks are better with single-glazed and conventional double glazing without low E coating, particularly on south-facing windows.Accordingly, expect strong market in retrofit (Private, Weatherization, Energy $mart) as well as with new buildings


Market magnitude in the US

63 million residential-style windows were sold in the US in 2003, 61% in new buildings, 39% in retrofit/remodelingAssuming 3% penetration of 133.7 million housing units, 4 million shutter systems would be sold in the year 2020.Snapshot in 2020: 5135 GWh cooling savings at site, 5.8 GW demand, 72.3 TBtu, $1 billion


Shutter open


Shutter closed


DevelopmentInitial work accomplished at the Syracuse Research Corporation in Syracuse, NY. Larry Kinney project leader; Greg Dike engineerFour phase project shortened to 1.5 phases due to U.S. Department of Energy cutbacksVery nice design achieved through extensive development and testing of prototypesShown to have excellent mechanical and thermal performance as well as weather resistance under wintertime conditionsAttractive economics for manufacturer and customer


Variety of shutter experiments at Syracuse Research Corp


Side view of sliding and air-sealing mechanisms


Subframe assembly with caulking and weatherstripping


Shutter assembly and roller details


Extrusions

Eight aluminum extrusions a key to the shutter systems designWork together with fin seals to facilitate easy sliding while remaining weather tightResult: exact fit of all parts; assembly time of 30 to 45 minutes; long lifetime of energy-saving serviceElegant simplicity


Details of new shutter model


Shutter female and male edges form weather-tight seal


Façade optionsOriginal prototypes used an ultraviolet-resistant plastic called “UVEC” vacuum formed to give the appearance of louversUV stabilized ABS will work well, too, large range of colors possibleVirtually any façade pattern is possible, not just the “standard” lookOther options include cementousboard for fire resistance, stamped metal for special effects, Kevlar™ for added security, FibAir® for daylighting


FibAir option

Provides diffuse daylighting function, insulation when closedMeasured visual transmittance of 0.4


Next steps for new prototypeModify extrusions to accommodate thicker insulation (polyisocyanurate), plus wood, stamped metal, Hardy Board®, Kevlar® or other facades if desiredComplete design of system to automate motorized movement mechanism using jack screw driveModify top extrusion to accommodate drive mechanism, control electronics, and power supplyDevelop wireless electronic boxes for shutters (receivers) and for controls inside (transmitters)


Elements of drive mechanism

Anticipate completely self-contained system requiring no physical connection to inside, simplifying installation, eliminating the need for an electricianSmall power supply at each shutter fueled by photovoltaics, charges battery or large capacitor, actuates gear motorNorth facades in northern hemisphere may need power from other shutters


ControlsIndividual control remotely with simple wireless switch addressed to individual shutters in a homeMain control in home set up to respond to emergency (fire, wind, etc) as first priorityFire Scout UV device senses fire, not sunMain control also optimizes shutter configuration to achieve best-case energy efficiencyEmergency egress always possible even if electronics failIndividual window over-ride capability


Testing and showing at Alpen Windows in Boulder area; Demo with green builders, retrofit with homeowners

Nice showpiece for progressive green builders interested in getting ahead of the competition, achieving net zero energy buildings Attractive “gee whiz” as well as energy-saving featuresMonitoring to show savings and comfort advantages (evaluation simplified by shutter vsnon-shutter use testing on a single home)Custom finishes and sizes easy to achieve


Other applicationsRetrofit will work well, too; an elegant arrow to add to the retrofit options quiver

National Weatherization ProgramHome Performance with Energy StarProgressive remodeling contractors

Other applications include shuttering for a promising new generation of evaporative coolers


Other approaches and applications under consideration

Consider passive solar circumstances with substantial south-facing glazing without adequate spaces for sliding shutters; greenhousesSolutions include pocket doors, strategic hinging and folding (horizontally and vertically), etc.Common elements include control from within, energy optimization with override


Commercial and institutional applications coming soon…The use of operable insulation to reduce heat losses and gainsduring unoccupied periods would be an effective way to negate theenergy penalty of large glazing areas, but cost, operation, andmaintenance are problematic.

To date, there is no effective equivalent of the shutter in modern commercial or institutional buildings.

Richard R. Janis, William K.Y. Tao Mechanical and Electrical Systems in Buildings, Third Edition“Sustainable Design,” page 617


Questions? Answers? Feedback? (Team also involved in Synertech Systems Corporation, www.SynertechSystemsCorp.com, and with Sunflower Corporation, a daylighting system development firm, www.sunflowercorp.biz)

Gary ClerResearch Engineer, [email protected]

John Hutson Electrical Engineer, biz guy [email protected]

Larry Kinney, PhDPresident, design [email protected]

Ross McCluney, PhDPhysicist, modeling &

evaluationrossm@synertechsystemscorp.

com

sbt insulating shutters - goozmo, boulder colorado … · temporary plywood) zdecoration ......

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